- Read on to hear from Wallaroos captain Michaela Leonard as a 17-year-old prepares to become Australia's youngest international
A high ankle sprain could deny Charlie Cale the chance to press his claims as a Wallabies bolter - but the ACT Brumbies will turn to the "top echelon of players in the world" for his replacement.
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Rob Valetini will shift back into the No.8 jersey to face the Crusaders at Canberra Stadium on Saturday, with an injury set to rule Cale out of action until the Super Rugby Pacific finals series.
The forward pack reshuffle sees Nick Frost named at flanker - with Darcy Swain and Cadeyrn Neville the starting locks - while Valetini moves to the back of the scrum.
Brumbies great Jeremy Paul says Valetini adds "world class" firepower to the ACT, and that's saying something considering the former played with "once in a lifetime" stars like George Smith, George Gregan and current coach Stephen Larkham.
"I've been a big fan of Rob Valetini for a long time. I watched this kid come through and you could just see, he was just earmarked to be a great," Paul said.
"Out of all the players, when you talk about world class - because we've obviously had some world class players here - when you talk about the top echelon of players in the world, Rob Valetini can be spoken about."
An injury weeks out from the finals is a cruel blow for Cale, who is on the verge of a new deal to stay in Canberra following his breakout Super Rugby season.
But Larkham is hopeful the 23-year-old could be back on the park before the quarter-finals as the Brumbies chase a top-two finish.
"We're hoping he'll be back before the finals, but realistically, I'd say it would be somewhere in the finals before we see him back," Larkham said.
"It's still going to be the same role for [Valetini]. He'll be in the back line for some lineout plays, he'll be off the back of the scrum for some scrum plays, and just his general ball carry around the paddock, the physicality he brings in defence and at the breakdown as well.
"We've got Frosty at six, so Frosty will be more of that lineout option. If you compare Bobby at six and Charlie at eight, Charlie was a lineout option so we've swapped that around."
The Crusaders have won just two games this year but sit three points outside the top eight, leaving Rob Penney's side with everything to play for in the final three rounds of the regular season.
The Brumbies are sitting third and - as the club celebrates a 20-year reunion of a 2004 grand final win over the Crusaders this week - they are desperate to climb into the top two to put themselves in the box seat for a home semi-final.
"We're there or thereabouts in the competition every year, but we haven't won it. We won Super Rugby AU, but the boys in this group who were a part of that campaign still don't recognise that as a proper victory because it's the New Zealand teams we always strive to beat," Larkham said.
"It's been 20 years and we've been close. If you go back to the early days of the Brumbies, we were good from 1996, '97, '98 onwards, but we didn't win it until 2001 and then we backed it up in 2004.
"Our challenge is, this year we're chasing a top two finish which helps you massively. You get a home quarter-final, and you potentially get a home semi-final as well. We know when we get a good crowd, it lifts the confidence of the players and they put a better performance out there."
LEONARD EYES WALLAROOS BOUNCE BACK
Michaela Leonard finds herself preparing for a Test match in an Australian rules heartland. Wondering how the Wallaroos captain can "win some AFL players over to get their bums in seats and show them how good this game can be"?
How about a 17-year-old fullback destined to become the youngest player to ever lace up the boots for the Wallaroos or the Wallabies? Or a powerhouse prop who might just lay claim to the greatest prop try of all time?
Rookie fullback Caitlyn Halse is poised to make her Test debut in the Wallaroos' Pacific Four series clash against the United States in Melbourne on Friday.
At 17 years and 242 days, Halse will shatter the record set by Sharyn Williams, who debuted at 18 years and 44 days some 30 years ago.
She is joined in Australia's starting XV by a "phenomenally physical" tighthead prop in Eva Karpani, and Leonard cannot wait to see the pair unleashed.
"The growth and the development in Caitlyn over the last 12 months, being part of some of our World XV campaigns last year and then coming into this year, she's really matured as a player on the field and off the field," Leonard said.
"I think her composure on field now and her ability to communicate has grown in leaps and bounds. I'm definitely excited for her to bring that out onto the field and then show what an attacking threat she can be with ball in hand as well."
The Wallaroos thrashed the United States last year, but both sides arrive in Melbourne as last-start losers. Australia were beaten by Canada in Sydney while New Zealand belted the USA in their tournament opener.
"We definitely expect them to come out strong. This is Test match footy and it's anyone's game," Leonard said.
"Definitely not underestimating at all. We know it's going to be a physical battle and we know that we've got to play our best footy to be able to come away with a win.
We've done really well this week to shore up a few of our areas around set piece, particularly the scrum and our maul defence. We want to make those weapons of ours. Lots of work in that area this week, lots of chat, lots of action towards becoming more physical. Hopefully we'll see that all game."